Pops and spikes w/DP 6.02

[mcevilley]

I'm running DP 6.02, on a Mac 2x2.8 Quad-Core Intel Xeon computer, with 8 gigs of ram. I have a UAD card, and various Waves plug-ins, I'm also using Trash, Mach V 2, Reaktor.
Lately, since I upgraded to DP 6 and my new Quad-Core computer, I've had a very strange problem with DP. This doesn't happen with every project, just every 4th or 5th project, I'd guess.
Anyway, for example, the current project I'm working on is only using about 10 tracks, 1 reverb and a delay. I'm only using a few waves plug ins. I can normally run many times this amount of tracks/plugs.
All of the sudden, every time my computer gets to measure, in this case, 14, I get a spike and pop sound. And, after working on the track trying to remedy the problem, I'm also getting a spike at measure 29. I check various soundbytes, and the pop somehow seems to be connected specifically to that location, and not necessarily that sound file.
My buffers are set at 1024. If I shift the all of the tracks 32 measures later, it still happens in the same place in the song. If I mute half of the tracks, it usually goes away. Strangely, it doesn't matter which half of the tracks I mute.

I've experienced something similar to this with various versions of DP throughout the years, although in the past it has been more of an isolated incident. With my current configuration, it seems to be fairly frequent.

All of the sound files I'm using have been recorded into the computer specifically for this project (guitars, pads from a Triton, and some vocals.) I wonder if one of the files has somehow become corrupt? If so, HOW? If not, what is going on?
Any suggestions would be appreciated.

[Jim]

Any suggestions would be appreciated.

I'd suggest you experiment with different buffer settings.

[mcevilley]

Really? I'm at 1024, so maybe 512 or even 256? Okay, I'll give it a try.

[Jim]

Really? I'm at 1024, so maybe 512 or even 256? Okay, I'll give it a try.

Well, you did say "any suggestion," and pops and crackles can often be traced to buffer settings. So, it can't hurt to experiment. And I think going smaller, as you say, 512 or 256 might help. Hope it works for you!

What's weird about your problem is that it occurs at the same spot in your playback. I'm sure you've zoomed into your waveforms at this point, and made certain that the pops weren't recorded, right?

[mcevilley]

Yes, I said "any suggestions," and I appreciate your suggestion. I'm going to try it in a few minutes.

I did zoom in on the waveform and the pop is not recorded.

[mcevilley]

Okay, I tried adjusting the buffer and it didn't affect the spike. It still occurred in the same place.

Thanks for the suggestion.

[Mark Walmsley]

You might try loading that sequence into a new file in case it has become corrupted.

[kassonica]

REading through your post I'd have to say that is has nothing to do with buffers.

I'd say you've clipped the convertors somehow on the way in.

How hot do you record?

Sometimes clips can't be picked up on the waveforms.

[mcevilley]

You might try loading that sequence into a new file in case it has become corrupted.

I believe this is the workaround solution MOTU suggested to me a few years back when this happened. That time it was an isolated incident. With my current configuration it seems to happen more often. I'd love to know how to avoid this, but in the mean time, yes, I suppose that's what I'll have to do.

Thanks for the suggestion.

[mcevilley]

REading through your post I'd have to say that is has nothing to do with buffers.

I'd say you've clipped the convertors somehow on the way in.

How hot do you record?

Sometimes clips can't be picked up on the waveforms.

I don't record very hot at all--between -6 and -12.

[kassonica]

REading through your post I'd have to say that is has nothing to do with buffers.

I'd say you've clipped the convertors somehow on the way in.

How hot do you record?

Sometimes clips can't be picked up on the waveforms.

I don't record very hot at all--between -6 and -12.

-6 is very hot.

[mcevilley]

REading through your post I'd have to say that is has nothing to do with buffers.

I'd say you've clipped the convertors somehow on the way in.

How hot do you record?

Sometimes clips can't be picked up on the waveforms.

I don't record very hot at all--between -6 and -12.

-6 is very hot.

No it isn't.

[kassonica]

I suggest you google intersample peaks.

Also between -20 and -16 dBFS equals 0VU.

But your telling me -6 isn't hot so they you go.

If your getting pops IN THE SAME PLACE EVERY TIME and your not running a lot of tracks and plugins it stands to reason that it's not your buffer.

[mcevilley]

I suggest you google intersample peaks.

Also between -20 and -16 dBFS equals 0VU.

But your telling me -6 isn't hot so they you go.

If your getting pops IN THE SAME PLACE EVERY TIME and your not running a lot of tracks and plugins it stands to reason that it's not your buffer.

Yeah, I didn't think it was my buffer, but I figured it was worth a shot since someone suggested it.

I appreciate your suggestion, kassonica, that I may be recording too hot. I've been recording at pretty much the same levels since DP first came out. I'm often given tracks that have already been recorded at much hotter levels (right up to 0), and I don't typically have any problems. So, there is really no point debating whether or not -6 is too hot or not. We can agree to disagree. The point is, the CPU meter, on the Audio Performance window, spikes at the same spot, whether or not I'm running any particular tracks. The CPU meter, on this particular project, is staying at around what I would guess to be 5-10% throughout playback, and then, all of the sudden, it hits the red, and causes a pop and even a tiny bit of silence and then continues on as if nothing happened--always at the same spot.

I was wondering if anyone else had experienced this, and if so, how one might avoid it.

[Artspoke]

Are your plug-ins running in realtime? Check in your preferences to make sure Plug-ins are set to run in realtime - this can be a real nuisance if it's not. Also, I notice horrible popping from many delay plug-ins whenever there's a tempo change. Have you tried disabling the plug to see if any is to blame? I found this post browsing for someone experiencing the same delay/tempo change popping. Can you see the pops on any of the meters?